[Cin] Anamorphic 16:9 SD-DV(D) widescreen to AV1.webm

Terje J. Hanssen terjejhanssen at gmail.com
Sun Jan 14 23:10:32 CET 2024



Den 14.01.2024 21:42, skrev Andrew Randrianasulu:
> On Sun, Jan 14, 2024 at 11:14 PM Terje J. Hanssen
> <terjejhanssen at gmail.com> wrote:
>>
>>
>> Den 14.01.2024 18:41, skrev Andrew Randrianasulu:
>>
>>
>>
>> вс, 14 янв. 2024 г., 19:51 Terje J. Hanssen <terjejhanssen at gmail.com>:
>>>
>>>
>>> Den 14.01.2024 17:43, skrev Terje J. Hanssen:
>>>
>>>
>>>
>>> Den 13.01.2024 18:48, skrev Andrew Randrianasulu:
>>>
>>>
>>>
>>> сб, 13 янв. 2024 г., 07:47 Andrew Randrianasulu <randrianasulu at gmail.com>:
>>>>
>>>>
>>>> сб, 13 янв. 2024 г., 03:26 Terje J. Hanssen via Cin <cin at lists.cinelerra-gg.org>:
>>>>>
>>>>>
>>>>> Den 11.01.2024 23:43, skrev Terje J. Hanssen:
>>>>>
>>>>> .......
>>>>>
>>>>>
>>>>> 4 a) Cin-GG
>>>>> Loaded a PAL 1080i/50 HDV clip
>>>>> Set Format Preset: PAL 576i (16:9) - DV(D)
>>>>> File Render File Format: FFmepg - avi   (NB! because plain Raw DV still causes DAR 4:3)
>>>>>                       Audio: Preset: avi_pcm_s16.avi
>>>>>                       Video: Compression: dv_pal.avi
>>>>>
>>>>>
>>>>> For me it looks like the Set Format Preset: PAL 576i (16:9) - DV(D and/or the File Format: FFmpeg make up the correct DAR 16:9 here, right?
>>>>>
>>>>> Because by Selecting the Format: Raw DV cause rendering to DAR 4:3 as shown below !
>>>>> This makes me wonder if it is only the FFmepg File formats that currently is fixed by patches?
>>>>> May also other non-FFmpeg formats be affected by anamorphic aspect ratios ?
>>>>
>>>> This is possible! I basically never used non-ffmpeg video encoders! I think we have 3 of them - raw dv, mpeg video and theora video.
>>>>
>>>> I'll check each of them.
>>>
>>>
>>> OOPS!
>>> As already mentioned, CinGG's FFmpeg-avi was saved/displayed 16:9 and the Raw DV was saved/displayed 4:3.
>>> BUT, in addition I discovered now that in both cases the images have been cropped around, that is cut off at both sides, top and bottom.
>>
>> I wonder how much was cropped?
>>
>> May be I misread you but you loaded HDV 1440*1080 clip and then rendered it into ffmpeg DV at 576i WITHOUT any scaling on top?
>>
>>
>> Yes, I loaded the anamorphic 16:9 HDV 1440x1080 clip and then rendered it using Set Format Preset PAL 576i (16:9)-DV(D) - without any scaling on top.
> I think only DVD/BD render adds scaling automatically on size mismatch ...
>
> so, for proper downscaling you need to apply it manually.
>

Learning by failing :)
DVD Render Format autoscales the input HDV format to fit the selected 
16x9 DVD output format.
When input format and output rendering formats are identical, it seems 
that nothing needs to be set/edited manually in Set Format.

Then the unavoidable request/suggestion:
Could correspondingly different I/O format via selected Presets also 
bake in Autoscale as default (beside color space mentioned before) ?
(refer to the: -vf scale=720:576,setsar=64/45,setdar=16/9 in the ffmpeg 
line below)

>> According to my understanding this should down-convert the full source image to DVD 16:9 anamorphic format, which at playback should display upscaled 16:9 screen.
>> That is, just as in my first post
>> 4 b) FFmpeg transcode HDV to DV-wide
>> ffmpeg -hide_banner -i hdv07_05.m2t -vf scale=720:576,setsar=64/45,setdar=16/9 -c:v dvvideo -c:a pcm_s16le dv07_05_wide.dv
>>
>> Gnome File properties and VLC Tools Codec info just say1440x1080 resolution for the HDV source and 720x576 for the CinGG rendered avi and dv output.
>> I don't know if it possible to find out exactly, but
>>
>> Visually I espect and will estimate that the "middle part" 720x576 px symmetrical around the center of the source image is kept. That is cropped away
>>
>> horizontally at each side: (1440-720)/2 = 360 px
>> vertically top and bottom: (1080-576)/2 = 252 px
>>
>>
>>
>>> That is, the 16:9 avi is displayed with correct geometry, while the 4:3 Raw DV is displayed stretched vertically.
>>> The latter get correct geometry if forced aspect 16:9 during VLC playback..
>>>
>>> Actually, only my ffmpeg manual encoded DV-wide has got correct DAR 16:9 and also correct geometry.
>>>
>>> And kept the full image (un-cropped).
>>>
>>>
>>> A visual tip is that this is easiest to discover and compare side by side using large file thumbnails with (Gnome) Filemanager.
>>>
>>>
>>> in cinelerra/fileogg.C I found this comment:
>>> =====
>>>
>>> if( asset->aspect_ratio > 0 ) {
>>>                  // Cinelerra uses frame aspect ratio, theora uses pixel aspect ratio
>>>    float pixel_aspect = asset->aspect_ratio / asset->width * asset->height;
>>>
>>>   aratio_num = pixel_aspect * 1000000;
>>>    aratio_den = 1000000;                                                                      }
>>>          else {
>>>   aratio_num = 1000000;
>>>
>>>   aratio_den = 1000000;                                                                      }
>>> =====
>>>
>>> strangely enough filedv seems to contain code to set is16x9 encoder flag ... not sure why it fails ....
>>>
>>> mpeg video also should honor aspect ratio, but not tested yet.
>>>
>>>
>>>
>>>>>
>>>>> mediainfo dv07_05_wide_cingg.dv | grep Display
>>>>>    Display aspect ratio                     : 4:3
>>>>>
>>>>> ffprobe -hide_banner dv07_05_wide_cingg.dv
>>>>> Input #0, dv, from 'dv07_05_wide_cingg.dv':
>>>>>    Duration: 00:06:58.08, start: 0.000000, bitrate: 28800 kb/s
>>>>>    Stream #0:0: Video: dvvideo, yuv420p, 720x576 [SAR 16:15 DAR 4:3], 25000 kb/s, 25 fps, 25 tbr, 25 tbn, 25 tbc
>>>>>    Stream #0:1: Audio: pcm_s16le, 48000 Hz, stereo, s16, 1536 kb/s
>>>>>
>>>>>
>>>>>
>>>>>
>>>>> --
>>>>> Cin mailing list
>>>>> Cin at lists.cinelerra-gg.org
>>>>> https://lists.cinelerra-gg.org/mailman/listinfo/cin
>>>
>>>



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